End-cell switch.



No. $310,958.# BATENTED JAN. 3o, 1906.

. LLYNDON.

BND CELL SWITCH.

` APPLICATION FILED '001'.17, 1904.

v l f 1 wom oz LAMAR 'LYNDoN z sHBBTs-SHBBT 1.

unirsi) -srirrns Parana* ormon- LAMAR` LYNDON, OF NEW YORK, N.. Y.,ASSIGNOR TO GENERL STORAGE i BATTERY COMPANY, O- F NEW YORK, N. Y., ACORPORATION OF NEW YORK.

END-CELL swiTcH.

Specication of Letters Patent. l

Patented Jan. 30, 1906.

i Application tiled October 1.7, 1904. Serial No. 228.671.

, To all whom it may concern:

Be it-known that I, LAMAR LYNDON, a citizen of the United States, and aresident of the borough of Manhattan, city, county, and State of NewYork, have in'vented certain new'and useful Improvements in End CellSwitches, of which the following is a specilticak tion.

after fully described and claimed in this specication and shown in theaccompanyin diarams loi.: circuits and apparatus num ered Fi ures 1 and2, and in Fig. 3, which is a detai View of a contact.

In systems using storage batteries in which variations in voltage acrossthe external circuit or variations of battery charge and dischar e areproduced by changing the number of ce ls in series, as by the use of anend-cell switch, those cells which are connected to the end-cellswitch-contacts are not discharged uniformly with the cells in the mainbody of the battery.

vIn charging the end cells it is customary to carry the end-cell switcharm or brush to the extreme outer cell-contact, thus placing all of thecells ofthe battery in series, and when charging has proceeded until theexe treme end cell gives indications of being i'ully charged theswitchearm is moved inward to the next adjacent cell-contact, thuscutting out theend cell or cells connected between the eXtreme contactand the one adjacent thereto. `The charging-currei'it will now ilowthrough the entire battery except the end cell or cells which have thusbeen cut out. When the next end cell or set of cells gives indicationsof being fully charged, the switch is again moved to the next adjacent.cell-contact, and this mode of operation is continued until the lastinner cell-contactis reached. It

by this time the cells in the main body oi the 1 battery are not fullycharged, charging is continued until they also indicate that they arefully charged, and then charging is discontinued.

Heretofore the end-cell switches designed for charging the cells asdescribed have been handoperated, and it has been diilicult to properlymaintain the end cells with sufficient charge. According to my inventionthe endcell-charging switch is automatic in its operations and is,furtherino e, responsive to changes in the condition of charge ofindividual cells or groups of cells in a battery, and it willautomatically set the contact-brush of the switch'upon such acell-contact that all the cells on one side of said contact are fullycharged and all on lthe other side have not been brought to full charge.As long as the cell or group oi cells connectedto the contact onwhichthe switch brush rests is fully .charged the switch willautomatically move to some other contact, cutting out those cells whichare charged and continuing .charging on those cells which have not yetbeen fully charged.

In the drawings only so much of the ele'ctric' circuits is siown asapplies to the end cells A and the automatic end-cell-charging switchcontrolling the cell-contacts 1 to l2, inclusive. The cells in the mainbody of the battery are indicated at B, and in a system of distributionemploying a storage battery the battery may be connected across the lineand used in connection with any desired auxiliary'apparatus, as abooster, in addition to the main generator or source of supply. Theswitch forming the subject-matter of this invention is designed to beused for charging purposes in addition to the usual end cell switch usedfor including more or less of the end cells in circuit with, the line,as the vol tage and current requirements may necessitate.

The switch-arm C, as shown, is duplex, be ing provided with thecontact-arms D and E, insulated from eachother by the insulation F andconnected to move together by suitable means along the series ofcontacts 1 to 12, inelusive. As shown, the contact-arm D makes contactwith the cell-contacts 1 to 12, inclusive, and also with a bus-bar G,while the other contact-arm E makes contact With the cell-contacts andwith a bus-bar H. As shown, the contact-armE does not bear upon IOO IOS

the bus-bar G, but is curved or bent in such manner that it passes overthe said bus-bar Without touching it.

Suitable means are provided for moving the switch-arm C in eitherdirection along the cell-contacts, as shown in this instance anactuating-motor T being provided, connected to operate a screw-shaft J',upon which the switch-arm C is mounted by means of screwsleeves K. Thecontact-arms D and E or brushes are suitably insulated from the sleevesK.

The iield of 'the motor I is preferably constantly excited in onedirection, and a reversing-switch L is connected to control thedirection of rotation of the motor-armature by suitable circuits andconnections.

An auxiliary genera tor 0, as shown, is connected between the innermostcontact 1 of the end cells A and the bus-bar G, suitable field-winding Pbeing provided for the generator O. The function ot the generator U tocharge the end cells as controlled by the switch-arm C.

The reversingsndtch L is provided with the controlling magnets orsolenoidsQ and R, provided with cores Q and l, connected to theswitch-arms S and T and provided with the retreating-springs U. Suitablecontacts 13, 14, and 15 are provided adapted to coperate with theswitch-arms S and T.

Current may be supplied to the motor l from any suitable source,(indicated by the mains c and 1),) which, as shown, are connected bywires 16 and 17 to the switch-contacts 13, 14:, and 15. The switch-armsS and T are in turn connected by wires 18 and 19 to the motor-terminals.It will be seen that according to the pair of contacts 13, 14., and 15,which the switch-arms S and T bear upon, the direction in which thecurrent is supplied to the motor will be controlled.

Suitable means are provided for controlling the energizing of thereversing-switch magnets Q and R, said means being in turn controlled bythe voltage between the busbars Gr and li, upon which the contact-arms Dand E bear, respectively. The voltage between the bus-bars G and ll isthe voltage ol' the cell or series ol cells connected between the twocontacts D and E. While any suitable means may be provided, in thisinstance a voltmeter V is so arranged and connected in circuit that itcontrols the magnets Q, and lt. The needle W ol' the voltlneter isinsulated l`rom the remaining parts and vprovided with cooperatinglinsulated contacts X and Y, which are connected, respectively, to themagnets Q, and lt by the wires 2U and 21 A branch circuit is led l'romthe positive main (I, to the insulated needle W, and the usualtcrininals 22 and .23 of the voltmeter are connected byfwires 24 and 25to the bus-bars Grand H, respectivel", in accordance with whicharrangement the voltneter indicates @resse the voltage between saidbus-bars. The cor-- respondin movement ot the needle W there toreconnects one or the other ol` the magnets Q R in circuit because saidmagnets are con nected to the positive main a b y the wire 26 and to thenegative main by wire 17.

vPreferably the distance between the brushes l) and E is substantiallyequal lo the pitch or distance vI'roir renter to center oll two oi thecontacts 1to l 2, inclusive, and each arm l) andEis provided with anauxiliary contact c, carried hy the main arm or insulated therelfrom byinsulation d. The auxiliary con.- tacts c are connected to the main armsthrough resistance c. The object oll this construction is to prevent theshort-circaiting ol' two el the cells.

The operation of the apparatus is as vtollows Let it he assumed that thedu ple); switcharm C is on the eX trein e outer contacts 1l and 12, asindicated in dotted lines in the drawings, contact-arm D bearing uponcontact 12 and contact-arm E bearing upon contact 11. in this positionof the switch-arm C current will pass from the dynamo O tlnmlgh busbarG, arm D, and contact 12 to and through. all of the end cells A back tocontact l and out to the negative brush of the generatin The excitationof the lield l? ot the auxiliary` dynamo U will be that du e to thevoltage impressed across the terminals ol the `held by all of the endcells in series, which voltage is sullie cient te produce anelectromotive force in the auxiliary dynamo large enough to send acharging-current through all of the cells A. When the cells connectedbetween the two contacts l1 and l2 upon which contact-arms 'E and D restreach substantially full charge, their voltage will have risen 'to sucha point that the needle Vr' ol the voltmetcr Y will be :aused to move inone direction or the other4---- as, for instance, toward the right-untilit comes into contact with contact The solenoid or magnet Q is then en\igized and closes switch L by moving contact-blades S and T uponcontacts 13 and l-l, thereby clos ing the circuit oi the motor l, whichrotates in. a direction to more the duplex brush C inward or toward theinner contact 1 ol' the end cells A. When the contzuft-arins .E and l)rest upon the next ljacent pair of contacts l0 and 1.1 of the series, il'the cells connected to said pair olt contacts, be substantially fullycharged the voltage will be high enough to maintain the needle ll" ofthe voltnnter against contact and the motor will con tinue to rotate uutil the contact-arms E and l) bear upon a pair ol contacts; ol theseries l to 1.2, between which the ,cells A. connected thereto are notlull'y charged and the voltage ol: which is insullicienl'f to maintainthe needle "N against contact X. lllihcn this point reached, themotor-circuit will be broken by the reversing-switch L and the brush Cwill be brought to rest hearing upon a pairof lOO ' the voltage in thecharging-circuit rises, due to the well-understood increase in batteryvoltage with increase of charge, a proportional infease' in theexcitation of the field P will take place, so that charging-current willbe maintained at its proper value. i if the brushv C comes to rest atcontacts near the extreme inner contact l1, all the cells connected withthose contacts between the brush C and contact 12 being .full and ifchar e and discharge of the battery should take p ace undertheseconditions, so that some or all of thecells bej tween the brush Candfcontact 12 should be discharged, then this discharge will also takeplace through the'cells lying between the pair of contacts at which thebrush C rests and the voltage of the cells between this pair of contactswill fall. The voltmeter-needle W will l therefore be deflected in theopposite directhis object.

, nert tion toward the left until'it makes contact with contact Y,thereby energizing solenoid or magnet R of the reversing-switch andcom-A leti'nga circuit between the motor I in such irectlon as to causethe motor to rotate to move ythe brushC outward, thus including a largernumber of cells thecharging-circuit. It will be seen that'in theconstruction and arrangement of the switching apparatus contact 1 isarranged beyond the possible travel of the brush C, so that thegenerator O will never be short-circuited, or any other suitable meansmay be 'provided for accomplishing y According to this invention it willbe seen that automatic chargin means are provided, whereb the end celsare automatically charge as required by the systenrmand this automaticchar ing means is automatically controlled b t e electric'conditions orpotential oi t e cells. The position of the charging-switch isautomatically changed to char e different cells as required in suchmanat any or all of the cells are automatically recharged as they becomedischarged beyond lav predetermined amount. .The actuatin means for theswitch is controlled by the vo tage of one or more o the cells, whichvolta e is 4impressed upon the bus-bars G and In the diagram of Fig. 2 amodification of the invention isshown, the object of which is to insurethat the brush moves from one contact to the next, no more and no less.It

-during the? time that the brush C is moving the needle' W of thevoltmeter should for any reason fall away from the contact X or Y, withwhich it coperates,it will be seen that locking the traveling sleeve tothe screwthreaded shaft J. As shown, upon the screwshaft J is atraveling internally-screw threaded sleeve 50, which is moved in onedirection or the other along shaft J, accordin to the direction ofrotation of the motor The sleeve 50 carries the duplex brush C, the armsD and E of which are suitably insulated therefrom. The traveling sleeve50, as shown, is loose within the switch-arms D and E, and means arerovided for automatically connecting said s eeve fast to the arms, sothat rotation of the shaft J will cause the sleeve to travel. As shown,the sleeve is provided with holes 63, with which a pin 64 is ada ted tocooperate. This pin 64 is control ed by a magnet 65, of which the pinforms the armature. Normally the in 64 is held out of engagement withone of t e holes 63 by the retracting-spring 66. When mag net 65 isenergized, the pin is moved into one of the holes63, and since themagnet is carried by the arm D and the two arms are secured together thesleeve and both arms will` be locked together. The voltmeter Visprovided with additional contacts X and Y with which the insulated end oof the needle W coperates. On the end-cell switchare arranged two, setsof auxiliary contact-buttons-1u and 2a, the pitch or distance apart ofthe buttons of each .set being equal to the pitch or distance fromcenter to center of the main contacts 1 to 12, inclusive, on the switch.The two sets 1'L and' 2 are spaced alternately, so that the distancefromA a contact l of4 one set to the next adjacent contact 2 of theother set is one-half the pitch or distance between the two contacts ofone set. All

` the contacts 1fl of one set and 2 of the other set' are electricallyconnected, as shownthat is to say, alternate contact-buttons. are joinedtogether. As shown, the series ol contacts 2U4 is connected by wire p tothe insulated end o ot' the needle W, while the series of contacts 1&1is connected bv Wire g7 to the auxiliarycontacts X and on tnevol'tmeter, whereby movement of the needle W to the right or left servesto connect wire p to wire (l, thereby connecting the sets of contacts land 2L with each other. is provided with a shoe or contact D', insulatedfrom the main )ortion of the brush and of slightly less widtli than thedistance bc- The main brush D 'siones tween two contact-buttons of oneseries of contactslthat is to say, the width of thel shoe D is less thanthe distance between two contacts 2 or two coi'itacts l, One of theseries ot contact-buttons is connected to one side of the system, as thenegative side, andthe other is not connected to any source of supplyexcept when the voltmetcrhand makes contact at X or Y. ln this instancelet it be assumed that the cells at the left-hand side ofthe series atA2 are negative, while the cells at the othei side or at the end cellsare positive or at the positive side of the storage battery. A positivewire connects the bus-har G with the contacts 13 and 15 of the reversingswitch L. A negative wire 71 connects the negative side A2 ol' th'eystorage battery to thc central contact is of the reversing-switch.Another wire 72 connects the series of contacts 2L with .the negativewire 71 said wire 72 being connected between the point 7 3 and thecontact 14 and including in its circuit the solenoid L2, provided withthe retracting-spring 7 4. Solenoid L2 controls a core 75, adapted tocoperatewit-h the cross-har of the reversingl switch and lock saidswitch in a given position as long as the magnet L2 is energized. Thewires 19, 20, and 21 connect the reversingsswitch with the voltmeter asbefore and connect the voltmeter-needle W with the main line. Motorconnections are also arranged as before.

The operation of the ap aratus in Fig. 2 is as follows: Il thcpotentiallacross the cells A, which are included between the brushes Dand E, increases to such a point that full charge of those cells to theright of the duplex brush is indicated, the voltnieter-needle W willmove, let us assume, to the right, in which ease contact will be madebetween the needle and contacts X and X. The motor l will be rotated tomove the duplex brush C in the proper direction. rl`he insulated contact0 ot' the needle W connects the series of contacts 1 to the wire p andthence by wire 72 and magnet L2 to the negative wire 71. Current maytherefore [low from the end cells A through contact-arm D, magnet 65,tothe shoe D. 'lhencei' said shoe is in the proper position current willlow through the wire connecting the series of contacts 1a and out to thenegative wire 71 by means of wire 72 and the magnet L2. The detent of'the magnet 65 is moved into posii tion to prevent the rotation ot thesleeve 50, l and the core 75 of magnet L2 locks the reversing-switch inthe desired position. As soon as the traveling sleeve 50 has moved ashort distance from the position shown iii Fig. 2 to a oint in whic i aportion oly the shoe D toue ics one ot' the contacts 2u a condition ofthe circuits is established siic'n that two iaths are provided for thecurrent passing through the magnets G5 and L2. One path is`from thepositive side of the circuiti through magnet 65 and shoe D to the contact 2, thence to the point 73, and out by wire 72 and magnet L2 to thenegative side of the circuit. The other path is from the shoe D throughthe wire-connecting contacts 1, thence through wires g and p to thepoint 73, and out through magnet L2. The movement of the sleeve 50will'theiefre continue as long as the shoe D touches any one of thecontacts 2L or as long as the 'voltmetcr hand or needle W holds theinsulated end 0 against the auxiliary contact X. If after the beginningof the movement of the sleeve 50 and duplex brush the voltineter-needleW should-` inovc away from the contacts a it is bearing, the motion ofthe s eeve 50 will not be stopped, because-the shoe D', bearing upon oneof the,contacts 2, enables a circuit to be completed directly to thepoint 73 and out f through magnet L2, circuit through the voltmeter handor needle W is broken. When the shoe D ofthe switch arm D finally movesto a position in which contact is not made with any of the contacte' 2,the circuit through the magnet L2 will be 9o broken and thereversing-switch released,` unless the voltineter-needle W stillcompletes the circuit. As soon as magnet Lz is de energized, as well asthe reversing-switch I magnet, the reversing-switch ar-Ins resume 95normal position, the current is switched oil' of the motor, and-thesleeve 50 immediately stops moving, although the momentum` of themotor-armature may cause the screw to make several turns after thecurrent has been switched ofi. The immediate stopping of the sleeve 50is due to the releas. ing of the sleevedetent bythe magnet 65.` If,onthe other hand, the voltmetei needle` or hand W bears against thecontacts X X' Y Y when the shoe D reaches the position as indicated inFig. 2, movement of the sleeve 50 will continue.

Obviousl any other suitable forni of appar.1 ratus may be substitutedfor the magnet L2 to control the reversing-switch L, and in'- stead of avoltnieter V, as indicated, any suitable form of eleetroresponsiveswitching device may he used which is responsive to the electricalcondition of the end cells A. One of the sets oi"' contacts 1" or 2a maybe eliminated by the usc'ot a spring-eontact like that shown in Fig. 3.This figure is a vertical sectional view ot' the s )ring-contactreteri'ed to, in which D, as begore, is the slice of the arm D and, asshown, is v)rovided with a depressed portion D3. The s oe D is adaptedto be moved to the right or'left over the spring-pressed button orcontact P', which moves iu the socket Q. The wires of the eircuits areled to the hinding-screws and 81,. 'lhe binding-screw 80 is inelectrical connect-- tion with the socket Q", and hence with contact P.'lhe binding-screw 81, as shown, is insulated from the support of thesocket ainst which 8o although the 85 reo rio

ardoise and is provided with a springcontact 8:?with which the plunger83, connected to contact P', is adapted to cooperate. As the shoe D ismoved 1n one direction or the other it will be seen that the contact Pis depressed, thereby moving 'the plunger 83 into contact with the'spring 82 arid completing the circuit between the shoe D and thebinding-screw S1. In the construction of contacts shown in Fig. 3 it isto be understood that the contacts P represent one yseries of contacts,as la, while the springs 82 represent the other series of contacts, as2a.

.The end-cell switchmay ofcourse be used in any connection in which itisfound applicable, either for charging or discharging-end cells, andappropriate changes may be made .in the circuits and lapparatus `toadapt the switch to different uses.

Obviously some features of this invention may be used without others,and the inven-l tion may be embodied in widely-varying forms.

Therefore,vwithout limiting myself to the constructions shown anddescribed nor enumerating equivalents, I claim, and desire to obtain byLetters Patent,tl1e following:

1. The combination with the end cells of a storage batter of reversiblecharging means havin@ a switc -brusl1, circuits and connections iaorautomatically controlling the charging means in accordance with theelectric condition of the l,enel cells, whercby the brush is moved ineither direction, and means for automatically determining the positionoi'` the brush in accordance with the electric condition of theendncells.

2. The combination with the end cells of astorage batter ,ofreversiblecharging means havin a switc 1-brush, circuits and connections orautomatically controlling the clnirging means in accordance-with thcpotential due to the electric condition ol the cud cells,`

whereby the` brush is moved in either dii-cction, and means forautomatically determining the position of the brush in accordance withthe electric condition of the end cells.

43. The combination with the end cells olE astorage battery,ofreversible charging moans havin a switc brush, circuits andconnections or automatically controllingr the charging means solely inaccordance with the electric condition oiE the end cells, whereby thebrush is moved in either direction, and means for automaticallydetermining lthe position of the brush in accordance with the electriccondition of the end cells.

4. The combination with the end cells ol a storage battery, and contactsconnected thereto, of reversible lharging means hav ing a switch-brush,circuits and connections for automatically controlling the chargingmeans in accordance with the potential er: isting between two of saidcontacts, whcrcl the brush is moved in` either direction, ai

means for automatically determining the position oi the brush -inaccordance with the electric condition ofthe end cells.

5. `The combination with the end cells of a storage battery, of areversibly-movable charging-switch having a switch-brush, meansautomatically controlled in accordance with the electric condition ofthe end cells for actuating said brush, and means for automaticallydetermining the position of the brush in accordance with the electriccondition of the end cells. 6. The combination with the end cells of a,storage battery, of reversible automatic charging means having aswitch-brush, circuits and connections whereby the osition of' thecharging means is automatical y changed tol charge di'derentcells' asrequired, and means for automatically determining the po-` sition of thebrush in accordance with variations in the electric condition of the endcells.

7. The combination with the end cells of a storage battery, ofreversible automatic charging means having a switch-brush, cir-I cuitsand connections so constructed and arranged that the charging means ismoved to automatically recharge any or all of the cells as they becomedischarged beyond a prede-I termined amount, and means for automaticallydetermining the position of the brush in accordance with the electriccondition of the end cells.

8. The combination with the endlcells of l a storage battery, of asource of supply for charging the same, a reversible switch i aving aswitch-brush controlling the charging ofsaid l 'end cells, means foractuating said switch,

means controlled b the voltage of one or more of the end cel s forautomatically controlling the switch-actuating means, and means forautomatically determining the position of'the switch-brush in accordancewith the electric condition of the end cells.

9. The combination of the end cells of a storage, battery continuouslyconnected to the worlvcircuit, charging means, and circuits andconnections for automatically controlling the` charging means inaccordance wi th the electric condition of' the end cells.

10. The combination with the end cells ot a storage battery, ofautomatic charging means, controllingcircuits and connections soarranged and constructed that said automatic charging means isshiftedrfrom any set of end cells to any other set and back again` asrceuircd, whcreh any or all of the end. cells are automatica lyrecharged as they become discharged beyond a predetermined amount.

ll.. The combination with the end cells of a storage battery, or asource of supply for charging the same, a switch controlling thecharging ci said end cells, means for actuating said switch, and meanscontrolled by the voltage particular individual end cells un- TOO IIO

dergoing charging for automatically controt iing the switch-actuatingmeans.`

i2. The combination with the cells ci storage hat ery, of a source ofcharging-current, cell-contacts and bus-hars, a duplex hrnsh havingcontacterms insulated from each other and adapted to connect diilercntcell-contacts to the hus-bars resoectively, means for actuating theduplex brush along the contacts in either direction, andren electrlcaidevice controlled cy the rolt-age loetween the hars due to the cellsYtor controlling 'the operation oi the crush-actuating meansl Thecombination with-the end cells of a strange battery, of a series otcontacts l e tween which the end colis are connected, a main andauxiliary bus-bars, a main contactarm adapted to connect successivecontacts to a main hns-har, an auxiliary inrush connected to move i.. ithe main crush at a deiinite distance therefrom and arranged to connect.successive cciitacts With an auxiliary bus-har, an electrical deviceconnected hetween thc main and auxiliary hns-hars, and means i'oractuatiiw' the main and auxiliary brushes in either d `cction, saidmeans being conti-oiled by the electrical device connected between thebus-hars, said device operating;` in accor-darme with -ariations involtage hetween said liars.

it. 'Ehe combination with the end cells oi' a storage battery, ofautomatic charging means, cimtroliing-circuits and connections thereforso constructed and arranged that the position oi the said chargingmcaiisis autmnaticaily changed to charge unterent coils as required, and meansior preventing the short-circuiting of the cells as the automaticcharging means is moved.

i5. '.lhe combination with the end cells of a stmage battery', of asource oll chargingcurrcnt, ccll-c nitacts and bus-hars, a duplex brushhaving,` contact-arms insulated l'rom cach other and adapted to connectdiilercnt cell-contacts to the bus-bars respectively, means loractuating the duplex brush alcunr the coni-acts iineither direction, aniectriral device controlled by the voltage between the hars due to thecells lor controlling The opera tion ol'ithe hr1sshfactlmting means, andelcctric-al means connected to the arms olsaid duplex brush i'ornrewniing short- :uiting oi the cud celisas tl. orush moi/cs,

iti. The combination with the end, cells ol a ure battery, oi an automatic charging switch, controlling-circuiis and, connections are,

i l l l l l i i l l i i l l .l i

therefor so constructed and arranged that the switch is moved toautomatically charge the colis as required by the system, and means forpreventing the stoppage oi said switch in its movement before it reachesthe proper position for charging.

i7. The combination with the a storage battery, means autonnrticallTcontrolled by the electric condition of the cells for actuating saidswitch, and means for preventing the stoppage ci'v the movement ol" theswitch beiorc the desired. position is reached.

1S. in an end-cell switch, the combination of at least two sets oiauxiliary contacts, a switch-arm, means for actuatingsaid arm, andcircuits amA connections so arranged that the switch-arm is actuated aslong as said sets of auxiliary contacts are electr' .rally connected,and continues to move to the desired position after said sets ol"contacts are disconnr-.ctedlll). nc combination oll the end cells of astorage hattery permanently connected inseries, automatic chargingmeans, circuits and connections therefor so arranged. and constructcdthat a variable number of said cells inserted in the churging-circuit,and automatic means For controlling` the position ol said charging meansin accordance with the electric condition oi the end cells.

2i). rthe combination with the end cells of a storage batterypermanently connected in series, oi automatic charging,r means, circuitsand connections therefor so arranged that the charging means is moved to'recharge the cells, and automatic means lor determining the positionoi' said chargingr means in ac'- cordance with the degree oi' charge inthe individual cell which is last placed in circuit.

12 i. The combination with thc end cells oi a storage battery, ol' achargimr-switcl'i having a brush,

end cells of automatic means for actuating said cluiro'incT means, andcircuits and cohneriions so arranged and constructed that the movementci' the brush is proporiiomil to the change in the .stale ol. charge oitlu` cells and in a direction to include all cells falling below ainw-detcrmined charge.

in testimoniy 'whereof l have signed this speriliention in thepresent-,e ol two subscribuurh witnesses.

li/iivliil LYNDON.

ihruntsou,

of a charging-switch,

IOO

